A WAENING TO FAEMEES AGAINST 



LANTEENS 



TEAP 



CATCH FRIENDS AS WELL AS ENEMIES 



BY 



W. H. COARD, LL. D. 



DEPARTMENT OF AGRICULTURE, OTTAWA 



TRAP-LANTERNS, as destroyers of 

 insect pests, have been recently much 

 discussed in the northern and west- 

 ern portions of Canada as well as in the 

 United States, and by the most persistent 

 and unscrupulous advertising a certain 

 " moth catcher " has been forced into undue 

 prominence, so that fruit growers and farm- 

 ers have been induced to buy in spite of the 

 protest of those who have thoroughly and 

 scientifically tested such devices. So im- 

 portant has this matter become that the 

 Entomological Division of Cornell University 

 has issued the result of experiments carried 

 out with trap-lanterns during three years, 

 containing in substance the following points : 

 Many kinds of insects are most active at 

 night and are then often attracted to any 

 light, but there are hosts of insects that fly 

 mostly in the daytime. Most of the grass- 

 hoppers, many of the true bugs (like the 

 squash stink bug), all of the butterflies (like 

 the very destructive cabbage butterfly), many 

 of the moths (like the peach tree borer moth), 

 many of the beetles (like the Colorado pota- 

 to beetle), most of the flies (like the house 

 fly), and many of the hymenoptera (like the 

 saw flies), are day fliers or are not attracted 

 to lights, and these include a large propor- 

 tion of our common insect pests. 



While a trap lantern or " moth catcher" 

 may attract and kill ten or twenty thousand 

 insects in a season, most of the household 

 pests, most of the fruit growers' insect 

 enemies, and nearly all the serious pests of 



the gardener or grower of general field crops 

 will fail to be trapped. Only winged adult 

 insects are caught, the more destructive 

 nymphs and larvae are never taken. Usually 

 moths will constitute about half of the in- 

 sects caught in trap lanterns, and most of 

 these are not pests, only ten per cent, of 

 those that are injurious are females, and 

 these have nearly all laid their eggs. Often 

 as many friends as foes among the beetles 

 will be taken. Nearly one-third of all the 

 insects caught in three months in two 

 "moth catchers," run in Canada, were 

 beneficial, and nearly as many friends as 

 foes were caught in the trap-lanterns. As 

 one of these parasitic insects' friends is ca- 

 pable of killing several injurious insects, the 

 prospect ot capturing so many beneficial in- 

 sects become a serious factor in considering 

 the advisability of using trap-lanterns. It 

 is not so much a question of how many in- 

 sects as of what kind of insects will be cap- 

 tured. 



Experience shows an orchardist or a 

 grower of small fruits has no use for a trap- 

 lantern or a " moth-catcher," because they 

 will not catch enough of the more injurious 

 fruit pests to pay one-tenth of the trouble 

 and expense of running them. Tent-cater- 

 pillar moths are the only common fruit in- 

 sects that are caught in economic numbers, 

 and nine-tenths of these will be males. Cod- 

 ling-moths are not attracted by lights, and 

 only rarely one accidently falls a victim. 

 The highest record in the Cornell experi- 



